Decreased Serum Level of miR-155 is Associated with Obesity and its Related Metabolic Traits.

BACKGROUND: Type 2 diabetes is the most common metabolic disease, affecting many of the adult population all around the world. In recent years much attention has been paid to the role of circulating miRNAs as novel biomarkers for various diseases. The aim of this study was to investigate the expression level of miR-155 in serum samples of diabetic and healthy subjects. METHODS: 42 healthy and 45 type 2 diabetic subjects participated in the study. Serum miR-155 level of the subjects was measured using real-time PCR. The levels of IL-6 and TNF-α were quantified using ELISA. RESULTS: There was no significant difference in the level of miR-155 between the diabetic and non-diabetic groups. The level of miR-155 in non-diabetic obese group was significantly lower than the non-diabetic lean subjects. Correlation analyses in non-diabetic group revealed a significant negative correlation between the amount of miR155 and body mass index and cholesterol levels after the elimination of the confounding factors. In diabetic group, a negative correlation was found between miR-155 and insulin, HOMA-IR, and waist circumference levels. Furthermore, no significant relationship between miR-155 and inflammatory cytokines (TNF-α and IL-6) was observed in both diabetic and healthy groups. CONCLUSIONS: A reduced level of miR-155 might associate with obesity and its related metabolic traits such as hyperinsulinemia and dyslipidemia.